Pronghorn Antelope are year-round residents on the INEEL, though in severe winter seasons pronghorns from throughout the state and as far away as Montana migrate to the INEEL. 

Pronghorns are the only member of its family, Antilocapridae. The pronghorn is extremely fast, with a top speed of about 60 miles per hour, and can easily outrun any other animal that tries to catch it.

The pronghorn has dark brown hair on its back and sides with lighter colored hair on its belly, throat and rump patch. A male has black cheek patches, some black over his face, and black horns.